FOCUS: Leaves come in a variety of shapes and sizes, but they are all designed to make food for the plant, using sunlight, water, air, and their green pigment, chlorophyll. With close observation, leaf features such as shape and venation can provide important clues to the identity of plants.
INTRODUCTION: LEAF GRAB BAG
Objective: To begin to explore and ask questions about leaves.
WARNING: Before collecting leaves, be sure to check your school grounds for any poisonous plants, such as poison ivy, wild parsnip, and chervil.
Have children work in small groups with a leader to look for different types of leaves. Provide paper lunch bags to collect samples. Ask them to collect leaves from different types of plants, such as grasses, weeds, trees, shrubs, even garden plants. Have each small group sort their leaves into two piles and see if the other groups can guess which feature was used to sort them.
Have the children save their leaves for future activities.
Materials: paper lunch bags, Fact Sheet on Poison Ivy, Wild Parsnip, and Chervil.
LEAF LOOK SORT AND FIND
Objective: To identify physical features of leaves and associated vocabulary.
Have each child choose a leaf from their Leaf Grab Bags (see Introduction above). Using the Leaf Anatomy and A Variety of Leaves diagrams, have them note the various features on their leaf. Explain that you will now be asking them to split into two groups based on one particular leaf feature. Possible leaf features to sort by include:
Big vs. small leaves
Smooth leaf edges vs. toothed edges
Entire leaf vs. leaves divided into lobes
Compound vs. simple leaves
Short vs. long petiole
Smooth surface texture vs. rough texture
Once they are in their groups, ask them to compare their leaves, noting variations among that particular feature. You may want to sort again, using another leaf feature. Have older children keep track of features that make their leaf unique. After sorting, have the children sit in circle with their group and collect their leaves. Spread their leaves in the center and have each child pick out their leaf, noting the features that helped them identify it.
Materials: assortment of leaves from Introduction: Leaf Grab Bag; Leaf Anatomy diagram, A Variety of Leaves diagram.
Objective: To learn about venation patterns in leaves.
Give children leaves and have them inspect the underside, noting the patterns of veins that run from petiole to leaf tip. Explain that these veins are like the plumbing system of the leaf; they transport water and minerals into the leaf and carry food out. Use the Three Leaf Venation Types diagram to show the three main venation patterns: pinnate, palmate, or parallel.
Pass out paper and have the children make a leaf print using crayons. Have them fold a piece of white paper in half. Place leaf, vein side up, in between. Using the broad side of the crayon, rub it over the enclosed leaf and an impression of the leaf and its vein pattern will appear.
Set out the Three Leaf Venation Types diagram depicting the three types of leaf venation – palmate, parallel, and pinnate. Ask children to place their leaf prints in line next to the matching venation type to create a bar graph, noting which type is most and least common among the leaves collected.
Materials: assortment of leaves from Introduction: Leaf Grab Bag, paper, peeled crayons, Three Leaf Venation Types diagram.
LEAF EYE SPY
Objective: To accurately identify and describe key physical characteristics of leaves.
Working in groups of three or four, have the children sit in a circle with leaves from the Introduction: Leaf Grab Bag activity spread out in the center. Explain that, one at a time, each child will choose one leaf to describe to the other children, without pointing it out, to see if the others can guess which one it is. The child describing the leaf should focus on one feature at a time. For example, “I spy with my little eye a leaf that has smooth edges.” After each feature is described, the children guessing then remove all the leaves that don’t match that description. This is a good strategy to help narrow down the leaf choices. Continue until the children correctly identify the “eye spy” leaf. Return all the leaves to the center of the circle and play again with a new child choosing and describing a secret leaf.
Materials: leaves from Introduction: Leaf Grab Bag activity.
PUPPET SHOW “Leaf It to Leaves”
Objective: To learn about variety in leaves and their common function.
Perform the puppet show, or have a group of children perform it for the class. Afterward, ask questions to review the key details and vocabulary in the story. What were some of the different kinds of leaves in the puppet show? (Frond, needle, blade.) What makes leaves green? (Chlorophyll.) What important job do leaves do for the plant? (Capture the sun’s energy and make food for the plant.) For older children, use the Photosynthesis Diagram and Photosynthesis Explanation to review the photosynthesis process and its importance to both plants and animals.
Materials: puppets, props, script, Photosynthesis Diagram and Explanation.
Objective: To create collages of animals using different shaped leaves.
Explain to the children that they will be using leaves of different shapes and colors to create pictures of insects or other animals. Show examples and ask questions to guide them in their leaf selection process.
What leaf shape reminds you of wings of a butterfly? Ears? Fins? Legs? A tail?
What shape leaf could be the abdomen of a bumblebee? Eyes of a dragonfly?
How could you give an animal spots using leaves? What about stripes?
Give children each a piece of cardstock and a glue stick to assemble a leaf collage animal.
If you press an assortment of leaves beforehand, they will retain their shape and color and last longer. You can also try pressing the final creations.
Materials: Leaf Critter examples, leaves – both newly collected and from Introduction: Leaf Grab Bag activity; cardstock and glue sticks.
UPPER GRADES CHALLENGE: Picture A Leaf (Grade 5-6)
Objective: To identify and describe key physical features of a leaf and communicate this information verbally.
Divide the group into pairs and have children sit back to back. Provide one child with a clipboard, pencil, and paper while the other secretly picks out a leaf from their Leaf Grab Bag (see Introduction above). With both children using the Leaf Anatomy and A Variety of Leaves diagrams as a guide, have one child describe a leaf, using vocabulary from the lesson, while the other tries to draw it based on the description. Compare the finished drawing to the chosen leaf. Switch roles and repeat the activity with a new leaf.
Materials: for each pair: leaves from the Introduction: Leaf Grab Bag; paper, pencil, clipboard, Leaf Anatomy and A Variety of Leaves diagrams.
JOURNAL ACTIVITY AND CLOSING THOUGHTS
Objective: To record observations about leaves.
There are several options for journal activities. For children in grades K-2, consider Leaf Prints and Leaf Critters. For children in grades 3-6, Leaf Prints, Leaf Critters, and Upper Grades Challenge: Picture a Leaf would be good choices. Afterward, in small groups, have children share their work and one thing they learned about leaves.
Materials: science journals or clipboards and paper; drawing materials.
A STEP BEYOND
Leaf Prints: Try making detailed leaf prints by using paint and roller brayers. Begin by applying paint or ink to a flat surface. Use the brayer to spread the paint in a thin film and direct children to use this supply to re-ink the brayer after each leaf. Have a child to place a leaf, vein-side up on a piece of paper and, using the brayer, spread a thin layer of paint all over the leaf surface. Have the child carefully remove the leaf, place it paint-side down on another sheet of white paper and cover it with a clean paper towel or a piece of scrap paper. Roll a second clean brayer over the leaf, remove the scrap paper, and gently lift off the leaf to reveal the vein print.
Fall Tree Leaf Collections: Take students outside to areas where different kinds of trees are growing. In small groups, have students collect leaves, choosing a variety of shapes and colors. Ask students to sort their leaf collections into groups based on color only. Then have them further divide these larger color groups into smaller groups based on leaf shape and vein patterns.
Note which leaves come in only one color and which come in a wider range of colors.
Have students try using the Fall Tree Leaf Identification Guide to identify the leaves.
As a closing activity, have small groups line up ten leaves of each tree species identified, highlighting either their uniformity of fall color or variation of hues.